Electrode assembly and lithium secondary battery with same

Abstract

An electrode assembly and a lithium secondary battery comprising the same are disclosed.Specifically, the present invention provides an electrode assembly which is capable of preventing the occurrence of a short circuit between a non-coating portion of an electrode plate and an active material layer of an electrode plate having an opposite polarity when damage or shrinkage of a separator takes place, through the attachment of an insulating tape to either or both sides of the non-coating portion of an electrode plate without attachment of an electrode tab.Therefore, an internal short circuit of the battery can be prevented by application of the electrode assembly of the present invention to a variety of lithium secondary batteries including pouch-type, polygonal and cylindrical batteries.

Description

RELATED APPLICATIONS[0001]This application claims the benefit of U.S. Provisional Application Ser. No. 61 / 074,566, entitled Electrode Assembly and Lithium Secondary Battery With the Same, filed Jun. 20, 2008 and hereby incorporated by reference in its entirety.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to a secondary battery. More specifically, the present invention relates to an electrode assembly and a lithium secondary battery comprising the same.[0004]2. Description of the Related Art[0005]Generally, the lithium secondary battery employs lithium-based oxide as a positive electrode active material and a carbon material as a negative electrode active material. Further, the lithium secondary batteries may be broadly classified into a liquid electrolyte battery and a polymer electrolyte battery, depending on the type of electrolytes used in them. The lithium battery using a liquid electrolyte is known as a lithium ion battery, and t...

AI Technical Summary

Benefits of technology

The present invention relates to a battery assembly and an electrode assembly that can prevent short circuits and improve safety. The invention achieves this by insulating the non-coated portion of an electrode plate with an insulating member, such as an insulating tube or an insulating label, that does not attach an electrode tab to the non-coated portion. This prevents exposure of the non-coated portion to the active material layer of an electrode plate having an opposite polarity. The invention also includes a method of forming an electrode assembly by coating a portion of a first electrode with a first electrode coating material so as to define a coated portion and at least one non-coated portion having a length, and coating a portion of the second electrode with a second electrode coating material so as to define a coated portion and at least one non-coated portion having a length. The invention improves safety by preventing short circuits and reducing the risk of internal heat generation.

Problems solved by technology

Unfortunately, even though an insulating tape is provided on an electrode tab-fixed region in the non-coating portions formed on both ends of the electrode plate, an internal short circuit may occur due to non-coating portion / non coating portion contact or non-coating portion / active material layer contact between electrode plates of opposite polarities, when damage or shrinkage of a separator occurs due to internal or external impact or heat generation.

Further, the non-coating portion without provision of the electrode tab is more highly susceptible to the occurrence of an internal short circuit, due to probable contact with the non-coating portion or active material layer of the electrode plate having an opposite polarity.

Particularly when the non-coating portion of the electrode plate is in contact with the active material layer of the electrode plate having an opposite polarity, it may cause fatal damage to thereby result in the danger of ignition or explosion of the battery.

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